4EO8:
reference: Tri-substituted acylhydrazines as tertiary amide bioisosteres: HCV NS5B polymerase inhibitors., Canales E, Carlson JS, Appleby T, Fenaux M, Lee J, Tian Y, Tirunagari N, Wong M, Watkins WJ, Bioorg Med Chem Lett. 2012 Jul 1;22(13):4288-92. Epub 2012 May 17. PMID: 22664130

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).